Speed selector devices



April 10, 1962 R. VETSCH 3,028,753

' I SPEED SELECTOR DEVICES Filed May 18. 1960 2 Sheets-Sheet 1 firm a? 2 INVENTOR.

N BY PUDOLF V TSCH flrromv'ys rice 3,028,763 SPEED SELECTOR DEVICES Rudolf Vetsch, Walton Hills, Ohio, assignor to The Warner & Swasey Company, Cleveland, Ohio, a corporation of Ohio Filed May 18, 1960, Ser. No. 29,851 7 Claims. (Cl. 74-371) This invention relates to speed selector devices and has particular relation to speed selector devices for selectively keying to a rotatable shaft in a transmission systehmf one of a plurality of gears mounted loosely on the s a t.

According to the invention, a keying device of novel and improved construction is provided for selectively keying to a rotatable shaft in a transmission system one of a plurality of gears which are loosely mounted on the shaft.

The device is arranged so that the keying operation is effected in response to relative movement between the keying device and the gears longitudinally of the shaft. Preferably, the keying device is movable relative to the gears to effect the keying operation. However, an arrangement may be provided wherein the gears are moved relative to the keying device if so desired.

The keying device is arranged such that a selected gear is keyed to the shaft by a minimum amount of movement of the keying device longitudinally of the shaft. For this purpose the keying device includes a key having a plurality of keying projections at one side thereof and the key is mounted for pivotal movement at One of its ends about an axis generally perpendicular to the shaft. Means are provided to pivot the key during movement thereof longitudinally of the shaft so that one of the projections is moved into keying relation with a gear.

In the preferred embodiment of the invention, the shaft which loosely mounts the gears is formed with a longitudinally extending slot and the keying device includes a double-ended key positioned within the slot and having two keying projections extending from a common side thereof. These projections are configured to project into key slots formed in the gears which communicate with the slot of the shaft and the spacing of the projections is such that they cannot simultaneously be positioned within key slots of the gears. A resilient member is mounted at the opposite side of the key to engage the shaft'for urging one or the other of the projections into the slot of the selected gear. A link is pivotally connected at one of its ends to the key and is pivotally connected at the other of its ends to an actuator which is slidable longitudinally of the shaft.

Means are provided to engage one of the keying projections when the keying device is moved longitudinally of the shaft to pivot the keying device for positioning the other projection within the slot of the selected gear under the action of the resilient means. Such means preferably comprise a plurality of washers spaced longitudinally of the shaft, and having projections extending into the slot of the shaft to engage the keying projections. The arrangement is such that when the keying device is moved longitudinally of the shaft, the projections of the washers engage camming surfaces of the keying projections to pivot the key to allow one of the keying projections to enter the slot of the selected gear.

It is, therefore, an object of the present invention to provide a novel and improved device for selectively keying to a shaft any one of a plurality of gears mounted loosely on the shaft.

It is another object of the invention to provide an improved keying device for selectively keying to a shaft any one of a plurality of gears loosely mounted on the shaft, including a key which is configured and arranged so that the keying operation is effected by a minimum relative movement between the gears and the keying device longitudinally of the shaft.

It is a further object of the invention to provide a device as defined in the preceding object wherein the key has a plurality of keying projections extending from a common side thereof, and resilient means extending from the other side thereof for urging one or the other of the keying projections into a key slot of the selected gear.

It is still another object of the invention to provide a change-speed mechanism including a rotatable shaft loosely mounting a plurality of gears, a keying device including a key mounted within a longitudinal slot of the shaft and having a plurality of keying projections extending from one side thereof to engage key slots of the gears, and a link pivotally connected to the key'at one end and pivotally connected at its other end to an actuator slidably mounted on the shaft to permit pivotal movement of the key during movement of the key relative to the gears along the shaft slot.

Other objects of the invention will become apparent from the following description taken in conjunction with the accompanying drawings in which similar reference,

characters designate corresponding parts and in which,

FIG. 1 is a view in section showing part of a transmission system including a keying device constructed in accordance with the present invention; and

FIGS. 2, 3 and 4 are views in section illustrating the keying device of FIG. 1 in three difierent positions each effective to key a separate gear to the shaft.

While a particular keying device is shown in the drawings and hereinafter described, it is to be understood that the invention is susceptible of other embodiments, constructions, and arrangements, and is particularly applicable to the selective keying to a rotatable shaft in a transmission assembly of one of a plurality of gears loosely mounted on the shaft. The keying device will be described in association with a transmission system utilized in a machine tool such as a lathe.

Referring now to the drawings, there is illustrated in FIG. 1 a transmission system in a machine tool including a rotatable shaft 10 which may constitute the feed shaft utilized for moving a tool supporting cross slide relative to a "workpiece in response to rotation of the feed shaft. The shaft 10 extends through an apron 11 of the machine tool, and has afiixed thereto a bevel gear 12 which meshes with a bevel gear 13 formed on a sleeve 14 which is keyed to a shaft 15 journaled for rotation by bearings 16 and 17 about an axis generally perpendicular to the axis of the shaft 10.

The shaft 15 may be referred to as the driw'ng shaft, and has loosely mounted thereon a pair of different size gears 18 and 19 which co-operate respectively with different size gears 20 and 21 formed on a sleeve 22 which is keyed to a shaft 23 journaled for rotation by bearings 24 and 25 about an axis generally parallel to the axis of the shaft 15.

The gears 18 and 19' are arranged to be selectively fixed to the shaft 15 so that the shaft 23 may be rotated from the shaft 15 at two different speeds. For this purpose a conventional speed selector device, represented generally by the numeral 26 is associated with the shaft 15. The device 26 is positioned within a longitudinally extending slot 27 of the shaft 15, and includes a key 28 pivotally connected at its one end to an actuator 29 by the connection 30. The actuator 29 is mounted on the shaft 15 for sliding movement longitudinally thereof and such sliding movement of the actuator may be effected in any suitable manner. At the other end of the key 28 is a keying projection 31 illustrated as extending into a slot 32 formed in the gear 18. A resilient member 33 shown in the form of a leaf spring is attached to the key 28 to engage the bottom wall of the slot 27 to bias the key 28 in a Patented Apr. 10, 1 962 counterciockwise direction about the pivot connection 30 and urge the projection 31 into the slot 32.

The projection 31 is formed by a straight upper surface 34 intermediate a pair of downwardly and outwardly inciined side surfaces 35 and 36. The side surfaces 35 and 36 are arranged to engage a projection 37 of a washer 33 which is positioned between the gears 18 and 19.

The key 28 is illustrated in FIG. 1 with the projection 31 extending into the slot 32 of the gear 13 and the gear 13 is thereby connected to the shaft 15 for rotation thercwith. If it is desired to connect the gear 19 to the shaft 15, the actuator 29 is moved in any suitable manner longitudinally of the shaft 15 toward the right as viewed in FIG. 1. During such movement the projection 37 of the washer 38 is engaged by the surface 36, and the key 23 is pivoted in a clockwise direction about the pivot connection 36 against the action of the spring 33 so that the projection 31 is withdrawn from the slot 32. Continued longitudinal movement of the key 28 toward the right results in positioning of the projection 31 within a slot 39 formed in the gear 19 and the gear 39 is thereby connected to the shaft 15.

The shaft 23 has loosely mounted thereon a plurality of gears 40, 41, 42, and 43 of different sizes which mesh respectively with different size gears 44, 45, 46, and 47 formed on a sleeve 48 which is secured to a shaft 49 which may be referred to as the driven shaft. The driven shaft 49 is operatively connected to a tool-supporting cross slide of the machine tool, and is journaled by bearings 59 and 51 for rotation about an axis generally parallel to the axes of the shafts 15 and 23. In the illustrated embodiment, the shaft 4d may be driven from the shaft 15 at eight different speeds selectable by the selective keying of one of the gears 18 and 19 to the shaft 15 and one of the gears 46, 41, 42, and 43 to the shaft 23.

In order to selectively connect one of the gears 40, 41, 42, and 43 to the shaft 23, there is provided according to the present invention a novel and improved selector device represented generally by the numeral 52. The device 52 is positioned within a longitudinally extending slot 53 formed in the shaft 23 and consists of a key 54 of novel configuration pivotally connected as at 55 to one end of a link 56 having its other end pivotally connected as at 57 to an extension 53 carried by an actuator 59 slidably mounted on the shaft 23. The key 54 is slidable longitudinally of the shaft 23 and has a plurality of spaced projections formed thereon to extend into key slots formed in the several gears mounted on the shaft 23.

In the illustrated embodiment of the invention the key 54 includes a pair of projections 60 and 61 adapted to extend into slots 62, 63, 64, and 65 formed respectively in the gears 46, 41, 42, and 43. The projections 69' and 61 extend from a common side of the key 54-, and a resilient member in the form of a bowed leaf spring 66 is secured to the key at the opposite side thereof so that the bowed portion engages the bottom wall of the slot 53 in the shaft 23 for urging the projections 60 and 61 upwardly as viewed in FIG. 1.

The projections 60 and 61 are spaced longitudinally of the key 54 by a distance which differs from the distance between the center points of any pair of the gears 40, 41, 42, and 43. As a result, the projections 60 and 61 cannot simultaneously be positioned within key slots of a pair of such gears. Means are provided to engage one of the projections 60 and 61. when the other of such projections is in a key slot so that such other projection is positively urged into the key slot.

Each of the projections 60 and 61 includes a flat upper surface intermediate a pair of downwardly and outwardly inclined surfaces. As shown, the projection 60 has an upper straight surface 67 intermediate the inclined surfaces 68 and 69, whereas the projection 61 has an upper surface 70 between inclined surfaces 71 and 72. The inclined surfaces 68, 69, '71, and 72 are arranged to cooperate with washers 73, 74, 75, 76, and 77 located between adjacent ones of the gears and at the outer surface of the end gears 40 and 43 so that certain of the projections 78, 79, S8, S1, and formed respectively on these washers engage the inclined surfaces 63, 69, 71, and 72 during longitudinai movement of the device 52 relative to the shaft 23.

in PEG. 1 the device 52 is shown in a position wherein the projection 60 extends into the key slot 63 of the gear 41 to connect the gear 41 to the shaft 23. The projection 6i; is urged into the key slot 63 by the spring 66 and by the projection 82 of the washer 77 which engages the projection 61. If it is desired to disconnect the gear 41 from the shaft 23 and to connect the gear 43 to the shaft, the actuator 59 is displaced toward the left as viewed in FIG. l until the projection 61 extends into the slot 65 of the gear 43 as shown in FIG. 2. During such movement of the actuator 55 the inclined surface 68 of the projection 69 engages the projection 79 of the washer '74 whereupon the key 54 is pivoted in a counterciockwise direction about the axis 55, and the link 56 is pivoted in a clockwise direction about the axis 57 to displace the axis 55 downwardly and withdraw the projection 68 from the slot 63. When the projection 61 is disengaged from the projection 82 of the washer 77 and has entered the slot 65 under the action of the spring 66, the projection 79 of the washer 14 engages the surface 67 of the projection 66 to positively position the key 54 as shown in FIG. 2.

If it is desired to disconnect the gear 43 from the shaft 23 and to connect the gear 49 to the shaft, the actuator 59 is moved from its position shown in FIG. 2 toward the left to the position shown in FIG. 3. During this movement, the surface 71 of the projection 61 will engage the projection 81 of the washer 76 so that the key 54 will be pivoted in a clockwise direction about the axis 55, and the link 56 will be pivoted in a counterclockwise direction about the axis 57. The axis 55 is thereby moved upwardly and the projection 61 is withdrawn from the slot 65. Continuation of such movement results in extension of the projection 60 into the slot 62 of the gear 40 under the action of spring 66 as shown in FIG. 3. It is noted that the projection 81 of the washer 76 engages the projection 61 when the projection 60 extends into the slot 62 to positively retain the key in the position illustrated in FIG. 3.

If it is desired to disconnect the gear 40 from the shaft 23 and to connect the gear 42 to the shaft, the actuator 59 is moved toward the left from its position shown in FIG. 3 to the position illustrated in FIG. 4. During this movement of the actuator the projection 73 of the washer 73 engages the inclined surface 68 of the projection 60 which causes the key 54 to pivot about the axis 55 in a counterclockwise direction and the link 56 to pivot in a clockwise direction about the axis 57. The projection 60 is thereby withdrawn from the slot 62 and the projection 61 enters the slot 64 of the gear 42 under the action of spring 66. When the projection 61 is within the slot 64, the surface 67 of the projection 60 is engaged by the projection 78 of the washer 73 and the key is positively retained in the position shown in FIG. 4. The above described procedure can be reversed by sliding the key toward the right from its position shown in FIG. 4.

It is to be understood that other arrangements different than that illustrated may be employed for effecting relative movement between the gears on the shaft 23 and the selector device 52. Although four gears are shown in association with the device 52, it is understood that a greater or lesser number of gears than that illustrated may be employed in connection with the device 52. Also, the spacing of the projections 60 and 61 with respect to each other may differ from that shown.

The improved keying device 52 effects the selective connection of the gears 40, 41, 42 and 43 to the shaft 23 in response to a very small longitudinal relative movement between the gears and the keying device. The amount of longitudinal movement of the device 52 required to disconnect one gear from the shaft 23 and to connect another gear to the shaft 23 is observed to be approximately one-half the distance between the center points of adjacent ones of the gear. It is noted that a conventional key, such as the key 26, must be moved a distance substantially equal to the distance between center points of adjacent gears to effect a change in the gear connections.

Although the invention has been described with reference to certain specific embodiments thereof, numerous modifications are possible and it is desired to cover all modifications fallin within the spirit and scope of the appended claims.

Having thus described my invention, 1 claim:

1. A device for selectively keying to a rotatable shaft any one of a plurality of gears loosely mounted on the shaft, said device including a key having a plurality of spaced keying projections extending outwardly from a common side thereof for positioning within key slots of the gears, resilient means carried by the key and extending outwardly from the side opposite to said one side, and a link pivotally connected to one end of said key to permit pivotal movement of the key about an axis generally perpendicular to the direction of spacing of the keying projections.

2. A device for selectively keying to a rotatable shaft any one of a plurality of gears loosely mounted on the shaft, said device including a key having a plurality of spaced keying projections extending outwardly from a common side thereof for positioning within key slots of the gears, a bowed leaf spring carried by the key and extending outwardly from the side opposite to said one side, an actuator to be slidably mounted on the shaft, and a link having one end pivotally connected to one end of said key and having its other end pivotally connected to the actuator to permit pivotal movement of the link and key about axes generally perpendicular to the direction of spacing of said keying projections.

3. In a transmission system, a rotatably mounted shaft having a longitudinally extending slot, a plurality of gears loosely mounted on the shaft, each of said gears having a key slot communicating with the slot of the shaft, a gear selector device including a key positioned within the slot of the shaft, said key having a plurality of spaced keying projections extending from a common side thereof adapted for positioning within the key slots of the gears, resilient means carried by the key and ex-' tending outwardly from the side opposite to said common side in engagement with the bottom wall of the slot of the shaft, means mounting said key for pivotal movement about an axis generally perpendicular to the axis of said shaft, means for effecting relative movement between said selector device and said gears longitudinally of the shaft, and means for engaging one of said keying projections to pivot said key about said axis during relative movement between the selector device and the gears for positioning another of said keying projections within a key slot. 7

4. In a transmission system, a rotatably mounted shaft having a longitudinally extending slot, a plurality of gears loosely mounted on the shaft, each of said gears having a key slot communicating with the slot of the shaft, a gear selector device including a key positioned within the slot of the shaft, said key having a plurality of spaced keying projections extending from a common side thereof adapted for positioning within the key slots of the gears, resilient means carried by the key and extending outwardly from the side opposite to said common side in engagement with the bottom wall of the slot of the shaft, an actuator slidably mounted on said shaft for 6 moving said key relative to said gears longitudinally of said shaft, a link having one end pivotally connected to said key and having its other end pivotally connected to said actuator, and a plurality of washers positioned between adjacent ones of said gears and at the outer surfaces of the end gears, each of said washers having a projection extending into the slot of said shaft to engage one of said keying projections for pivoting said key in response to movement of said key relative to said gears longitudinally of the shaft for positioning another of the keying projections within a key slot.

5. A system as defined in claim 4 wherein said resilient means comprises a bowed leaf spring having ends engaging said opposite side and having a central portion bowed outwardly to engage said bottom wall.

6. In a transmission system, a rotatably mounted shaft having a longitudinally extending slot, a plurality of gears loosely mounted on the shaft, each of said gears having a key slot communicating with the slot of the shaft, a gear selector device including a key positioned within the slot of the shaft, said key having a plurality of spaced keying projections extending from a common side thereof adapted for positioning within the key slots of the gears, resilient means carried by the key and extending outwardly from the side opposite to said common side in engagement with the bottom wall of the slot of the shaft, means mounting said key for pivotal movement about an axis generally perpendicular to the axis of said shaft, means for effecting relative movement between said selector device and said gears longitudinally of the shaft, and a plurality of washers positioned between adjacent ones of said gears and at the outer surfaces of the end gears, each of said washers having a projection extending into the slot of said shaft for engaging one of said keying projections to pivot said key about said axis during relative movement between the selector device and the gears for positioning another of said keying projections within a key slot.

7. In a transmission system, a rotatably mounted shaft having a longitudinally extending slot, a plurality of gears loosely mounted on the shaft, each of said gears having a key slot communicating with the slot of the shaft, a gear selector device including a key positioned within the slot of the shaft, said key having a plurality of spaced keying projections extending from a common side thereof adapted for positioning within the key slots of the gears, resilient means carried by the key and extending outwardly from the side opposite to said common side in engagement with the bottom wall of the slot of the shaft,

an actuator surrounding said shaft for sliding movement therealong to move said key relative to said gears longitudinally of said shaft, a link within the slot of said shaft having one end pivotally connected to said key and having its other end pivotally connected to said actuator, and means for engagin one of said keying projections to pivot said key about said axis during relative movement between the selector device and the gears for positioning another of said keying projections within a key slot. 

